1. Field of the Invention
The invention relates to a friction stir welding apparatus comprising multiple sub-components which collectively perform as one integrated welding system allowing the apparatus to be operated and maintained in a variety of environments while permitting reduced size of the unit. The integrated nature of the sub-components gives the operator more flexibility in the type and size of workpiece that can be welded and effectively expands the utility of the friction stir welding process.
2. Description of Related Art
Friction stir welding is a method of welding based upon the principle of "rubbing" of articles to be joined together so as to generate a sufficient amount of heat. A probe of a harder material than the treated work pieces is typically applied in a welding process. The probe is subjected to cyclic movement relative to the work pieces. Merging the probe and work pieces together has been found to create a plasticized region in the work pieces due to generated frictional heat. When the relative cyclic movement of the probe stops, the plasticized material solidifies to create a weld joint.
The Friction Stir Weld (FSW) process, as it exists today, is believed to be limited to few manufacturing floors. Almost all known systems are restricted to laboratory/development environments. Development and laboratory equipment consists of large off-the-shelf machinery such as machining molds, modified to accommodate the FSW process. The large size of the laboratory equipment places size constraints upon manufacturing and tooling requirements, as a result, it is impractical and cost prohibitive to use machining mills for most manufacturing FSW applications. Additionally, the working envelope of the machining mills prohibits large pieces of hardware to be welded.